Medical balloon

ABSTRACT

Medical devices and methods for making and using medical devices are disclosed. An example medical device may include a catheter. The catheter may include a catheter shaft and a balloon. The balloon may comprise a cone portion, a waist portion, and a body portion. A fiber braid may be disposed along the balloon. An inner surface of the waist portion may be thermally bonded to an outer surface of the catheter shaft and an inner surface of the fiber braid may be adhesively bonded to an outer surface of the waist portion.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/484,922, filed Apr. 11, 2017, which claims the benefit of priorityunder 35 U.S.C. § 119 to U.S. Provisional Application Ser. No.62/321,394, filed Apr. 12, 2016, the entirety of which are incorporatedherein by reference.

TECHNICAL FIELD

The invention relates to intravascular medical devices such as medicalballoons and methods of making the same.

BACKGROUND

Medical balloons can be used to administer a variety of treatments. Forexample, in an angioplasty procedure, a balloon can be used to widen aconstricted bodily vessel, such as a coronary artery. A balloon can alsobe used to deliver a tubular member, such as a stent, that is placed inthe body to reinforce or to reopen a blocked vessel.

In angioplasty, the balloon can be used to treat a stenosis, or anarrowing of the bodily vessel, by collapsing the balloon and deliveringit to a region of the vessel that has been narrowed to such a degreethat blood flow is restricted. The balloon can be delivered to a targetsite by passing the catheter over an emplaced guidewire and advancingthe catheter to the site. In some cases, the path to the site can berather tortuous and/or narrow. Upon reaching the site, the balloon isthen expanded, e.g., by injecting a fluid into the interior of theballoon. Expanding the balloon can expand the stenosis radially so thatthe vessel can permit an increase in the rate of blood flow. After use,the balloon is collapsed and withdrawn.

In stent delivery, the stent is compacted on the balloon and transportedto a target site. Upon reaching the site, the balloon can be expanded todeform and to fix the stent at a predetermined position, e.g., incontact with the vessel wall. The balloon can then be collapsed andwithdrawn.

Medical balloons can be manufactured by extruding a cylindrical tube ofpolymer and then pressurizing the tube while heating to expand the tubeinto the shape of a balloon. The balloon can be fastened around theexterior of a hollow catheter shaft to form a balloon catheter. Thehollow interior of the balloon is in fluid communication with the hollowinterior of the shaft. The shaft may be used to provide a fluid supplyfor inflating the balloon or a vacuum for deflating the balloon.

SUMMARY

This disclosure provides design, material, manufacturing method, and usealternatives for medical devices. A catheter is disclosed. The cathetercomprises:

a catheter shaft;

a balloon, the balloon comprising a cone portion, a waist portion, and abody portion; and

a fiber braid disposed along at least a portion of the balloon;

wherein an inner surface of the waist portion is thermally bonded to anouter surface of the catheter shaft and an inner surface of the fiberbraid is adhesively bonded to an outer surface of the waist portion.

Alternatively or additionally to any of the embodiments above, furthercomprising a first thermoplastic polyurethane coating disposed betweenthe fiber braid and an outer surface of the balloon.

Alternatively or additionally to any of the embodiments above, furthercomprising a second thermoplastic polyurethane coating along an outersurface of the fiber braid.

Alternatively or additionally to any of the embodiments above, the fiberbraid includes an ultra high molecular weight polyethylene.

Alternatively or additionally to any of the embodiments above, theballoon is formed of a poly(ether-block-amide).

Alternatively or additionally to any of the embodiments above, theballoon includes an inner layer formed of a poly(ether-block-amide) andan outer layer formed of a polyamide.

Alternatively or additionally to any of the embodiments above, thecatheter shaft includes a polyamide.

Alternatively or additionally to any of the embodiments above, the fiberbraid is adhesively bonded to the outer surface of the waist portion ofthe balloon with a thermoset adhesive.

Alternatively or additionally to any of the embodiments above, thethermoset adhesive includes a moisture cure material, a UV curematerial, or a combination thereof.

Alternatively or additionally to any of the embodiments above, thecatheter shaft is a dual lumen catheter shaft.

A catheter is disclosed. The catheter comprises:

a polymeric catheter shaft;

a balloon having a cone portion, a waist portion, and a body portion,the balloon including a thermoplastic elastomer; and

a fiber braid disposed along the balloon, the fiber braid includingmolecularly oriented high molecular weight polymer;

wherein an inner surface of the waist portion is bonded to an outersurface of the polymeric catheter shaft using a first method and whereinan inner surface of the fiber braid is bonded to an outer surface of thewaist portion by a second method that is different than the first methodso as to preserve the molecular orientation of the molecularly orientedhigh molecular weight polymer of the fiber braid.

Alternatively or additionally to any of the embodiments above, the innersurface of the fiber braid is adhesive bonded to the outer surface ofthe waist portion.

Alternatively or additionally to any of the embodiments above, the outersurface of the polymeric catheter shaft is thermally bonded to the innersurface of the waist portion.

Alternatively or additionally to any of the embodiments above, thethermal bond between the outer surface of the polymeric catheter shaftand the inner surface of the waist portion forms an interface comprisingthe thermoplastic elastomer of the balloon and a polymeric material ofthe polymeric catheter shaft.

Alternatively or additionally to any of the embodiments above, thethermoplastic elastomer of the balloon and a polymer of the polymericcatheter shaft have a common monomer.

A method of making a catheter assembly is disclosed. The methodcomprises:

disposing a fiber braid about a balloon, the balloon comprising a coneportion, a waist portion and a body portion, the fiber braid beingterminated distally at a predetermined point relative to the waistportion;

disposing the balloon on a catheter shaft;

applying heat to at least a portion of the waist portion to thermallybond an inner surface of the fiber braid to an outer surface of thewaist portion; and

adhesively bonding the inner surface of the distal portion of the fiberbraid to the outer surface of the waist portion.

Alternatively or additionally to any of the embodiments above, furthercomprising trimming the waist portion to a predetermined length.

Alternatively or additionally to any of the embodiments above, theadhesive is applied after trimming the waist portion.

Alternatively or additionally to any of the embodiments above, wherein afirst section the fiber braid is supported by the waist portion and asecond section of the fiber braid extends distally beyond the waistportion such that the second section is unsupported by the waistportion, further comprising proximally retracting at least the secondsection of the fiber braid and a region of the first section of thefiber braid to expose at least some of the waist portion before applyingan adhesive, distally moving the second section of the fiber braid afterapplying the adhesive, and curing the adhesive.

Alternatively or additionally to any of the embodiments above, disposingthe balloon on a catheter shaft includes welding the waist portion tothe catheter shaft, braiding the fiber braid over the balloon and thecatheter shaft, trimming the fiber braid at a predetermined location,and applying the adhesive to the waist portion, to the inner surface ofthe fiber braid at the waist portion at the predetermined location, orboth.

The above summary of some embodiments is not intended to describe eachdisclosed embodiment or every implementation of the present disclosure.The Figures, and Detailed Description, which follow, more particularlyexemplify these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be more completely understood in consideration of thefollowing detailed description in connection with the accompanyingdrawings, in which:

FIG. 1 is a side view of an example medical device;

FIG. 2 is a partial cross-sectional side view of an example medicaldevice;

FIG. 3 is a cross-section of an example medical device taken at section3-3 in FIG. 2;

FIGS. 4-10 illustrate an example manufacturing process for an examplemedical device;

FIGS. 11-21 illustrate an example manufacturing process for an examplemedical device.

While the disclosure is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It should beunderstood, however, that the intention is not to limit the invention tothe particular embodiments described. On the contrary, the intention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the disclosure.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification.

All numeric values are herein assumed to be modified by the term“about,” whether or not explicitly indicated. The term “about” generallyrefers to a range of numbers that one of skill in the art would considerequivalent to the recited value (e.g., having the same function orresult). In many instances, the terms “about” may include numbers thatare rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and5).

As used in this specification and the appended claims, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

It is noted that references in the specification to “an embodiment”,“some embodiments”, “other embodiments”, etc., indicate that theembodiment described may include one or more particular features,structures, and/or characteristics. However, such recitations do notnecessarily mean that all embodiments include the particular features,structures, and/or characteristics. Additionally, when particularfeatures, structures, and/or characteristics are described in connectionwith one embodiment, it should be understood that such features,structures, and/or characteristics may also be used connection withother embodiments whether or not explicitly described unless clearlystated to the contrary.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The drawings, which are not necessarily to scale, depictillustrative embodiments and are not intended to limit the scope of thedisclosure.

As used herein, the terms “proximal” and “distal” refer to that which isclosest to the user such as a surgeon and that which is furthest fromthe user respectively.

A side view of an exemplary balloon catheter 11 is illustrated inFIG. 1. The balloon catheter 11 may include an expandable medicalballoon 10 having a fiber braid 20 disposed thereon and mounted on thedistal end of a catheter shaft 30. The catheter shaft 30 extends from amanifold assembly 40 at a proximal end of the catheter shaft 30. Theballoon 10 is shown having a body portion 12, a proximal cone portion 14a, a distal cone portion 14 b, a proximal waist portion 16 a, and adistal waist portion 16 b. The balloon 10 may be secured to the cathetershaft 30 at the proximal and distal waist portions 16 a and 16 b,respectively.

For the balloon catheter 11 shown in FIG. 1, the catheter shaft 30 isdepicted as a dual-lumen catheter shaft 30 that includes a guidewirelumen 32 for a guidewire (not shown) and an inflation lumen 34 forinflation of the balloon 10 as shown in cross-section in FIG. 3.Alternatively, the catheter shaft 30 may include an inner tubular memberdefining the guidewire lumen 32 and an outer tubular member extendingaround the inner tubular member. In these instances, the inflation lumen34 may be defined between the inner tubular member and the outer tubularmember. In such cases, the proximal waist portion 16 a may be secured toa distal end region of the outer tubular member and the distal waistportion 16 b may be secured to a distal end region of the inner tubularmember. Other catheter shafts are contemplated.

The balloon 10 may be pre-formed, for example, by radial expansion of atubular parison, which is optionally also longitudinally stretched. Theextruded parison may be radially expanded in a mold or by free-blowing.Alternatively, the parison may be pre-stretched longitudinally beforeexpansion or reformed in various ways to reduce thickness of the ballooncone and waist regions prior to radial expansion. The blowing processmay utilize pressurization under tension, followed by rapid dipping intoa heated fluid; a sequential dipping with differing pressurization; apulsed pressurization with compressible or incompressible fluid, afterthe material has been heated. Heating may also be accomplished byheating the pressurization fluid injected into the parison. The balloon10 may range in size from about 4 mm to about 26 mm.

The balloon 10 may be formed from typical balloon materials includingcompliant, semi-compliant, and non-compliant balloon materials. Thesematerials may include thermoplastic polymers, elastomers, andnon-elastomers. Such materials may include low, linear low, medium, andhigh density polyethylenes, polypropylenes, and copolymers andterpolymers thereof; polyurethanes; polyesters and copolyesters;polycarbonates; polyamides; thermoplastic polyimides; polyetherimides;polyetheretherketones (PEEK) and PES (polyether sulfone); and copolymersand terpolymers thereof. Physical blends and copolymers of suchmaterials may also be used. Examples of polyesters include, but are notlimited to, polyethylene terephthalate (PET), polyethylene naphthalate(PEN), polybutylene terephthalate, and copolymers thereof. Examples ofpolyamides which may be used include nylon 6, nylon 64, nylon 66, nylon610, nylon 610, nylon 612, nylon 46, nylon 9, nylon 10, nylon 11, nylon12, and mixtures thereof. Examples of suitable polyurethanes include,but are not limited to, aromatic polyether-based thermoplasticpolyurethanes (TPUs) such as those available under the tradename ofTecothane® from Thermedics; thermoplastic polyurethane elastomeravailable under the tradename of Pellethane®, such as Pellethane®2363-75D from Dow Chemical Co.; and high strength engineeringthermoplastic polyurethane available under the tradename of Isoplast®,such as Isoplast® 301 and 302 available from Dow Chemical Co.

In some embodiments, the balloon 10 may be formed frompoly(ether-block-amide) copolymers. The polyamide/polyether blockcopolymers are commonly identified by the acronym PEBA (polyether blockamide). The polyamide and polyether segments of these block copolymersmay be linked through amide linkages, or ester linked segmented polymers(e.g., polyamide/polyether polyesters). Suchpolyamide/polyether/polyester block copolymers are made by a moltenstate polycondensation reaction of a dicarboxylic polyamide and apolyether diol. The result is a short chain polyester made up of blocksof polyamide and polyether. Polymers of this type are commerciallyavailable under the tradename of Pebax® from Arkema. Specific exampleare the “33” series polymers with hardness 60 and above, Shore D scale,for example, Pebax® 6333, 7033, and 7233. These polymers are made up ofnylon 12 segments and poly(tetramethylene ether) segments linked byester groups.

Polyester/polyether segmented block copolymers may also be employedherein. Such polymers are made up of at least two polyester and at leasttwo polyether segments. The polyether segments are the same aspreviously described for the polyamide/polyether block copolymers usefulin the invention. The polyester segments are polyesters of an aromaticdicarboxylic acid and a two to four carbon diol.

In some embodiments, the polyether segments of the polyester/polyethersegmented block copolymers are aliphatic polyethers having at least 2and no more than 10 linear saturated aliphatic carbon atoms betweenether linkages. Ether segments may have 4-6 carbons between etherlinkages, and can be poly(tetramethylene ether) segments. Examples ofother polyethers which may be employed in place of or in addition totetramethylene ether segments include polyethylene glycol, polypropyleneglycol, poly(pentamethylene ether) and poly(hexamethylene ether). Thehydrocarbon portions of the polyether may be optionally branched. Anexample is the polyether of 2-ethylhexane diol. Generally such brancheswill contain no more than two carbon atoms. The molecular weight of thepolyether segments is suitably between about 400 and 2,500, such asbetween 650 and 1000.

In some embodiments, the polyester segments of the polyester/polyethersegmented block copolymers are polyesters of an aromatic dicarboxylicacid and a two to four carbon diol. Suitable dicarboxylic acids used toprepare the polyester segments of the polyester/polyether blockcopolymers are ortho-, meta-, or para-phthalic acid,napthalenedicarboxylic acid, or meta-terphenyl-4,4′-dicarboxylic acids.Specific examples of polyester/polyether block copolymers arepoly(butylene terephthalate)-block-poly(tetramethylene oxide) polymerssuch as Arnitel® EM 740, sold by DSM Engineering Plastics, and Hytrel®polymers, sold by DuPont, such as Hytrel® 8230.

The above lists are intended for illustrative purposes only, and not asa limitation on the present disclosure. It is within purview of those ofordinary skill in the art to select other polymers without departingfrom the scope of this disclosure.

The balloon 10 may be capable of being inflated to relative highpressures. For example, the balloon 10 may be inflated to pressures upto about 20 atm or more, or up to about 25 atm or more, or up to about30 atm or more, or up to about 40 atm or more, or up to about 45 atm ormore, or up to about 50 atm or more, or about 20-50 atm, or about 25-40atm, or about 30-50 atm. At such elevated pressures, the bond betweenthe proximal waist portion 16 a and the catheter shaft 30 (as well asthe bond between the distal waist portion 16 b and the catheter shaft30) is maintained. Furthermore, the bond between the fiber braid 20 andthe balloon 10 is also maintained at these elevated pressures.

In some embodiments, the balloon 10 is formed from a compliant material.In some embodiments, the balloon 10 is formed from an elastomer, such asa block copolymer elastomer. The block copolymer elastomer may be apoly(ether-block-amide) copolymer. The balloon can also be formed oflayers, for example, an inner layer formed of a first polymer materialand an outer layer formed from a second polymer material different thanthe first polymer material. For example, in some embodiments, the innerlayer may be formed from an elastomeric polymer material, for example, ablock copolymer elastomer, and the outer layer is formed from anon-elastomeric polymer material. In some embodiments, the inner layeris formed of a poly(ether-block-amide) copolymer; and the outer layer isformed of a polyamide.

The fiber braid 20 may be formed from a suitable polymer material.General classes of suitable fiber braid materials include, for example,polyesters, polyolefins, polyamides, polyurethanes, liquid crystalpolymers, polyimides, and mixtures thereof. More specific examplesinclude, but are not limited to, polyesters such as polyethyleneterephthalate (PET), polybutylene terephthalate (PBT), andpolytrimethylene terephthalate (PTT). Polyamides include nylons andaramids such as Kevlar®. Liquid crystal polymers include Vectran®.Polyolefins include ultrahigh molecular weight polyethylene, such asDyneema® sold by DSM Dyneema BVm Heerlen, Netherlands, Spectra® fibers,sold by Honeywell, and very high density polyethylene, and polypropylenefibers. Elastomeric fibers can be used in some cases.

In some embodiments, the fiber braid 20 comprises an ultra highmolecular weight polyethylene (UHMPE). Commercially available UHMPEsinclude, but are not limited to, Dyneema® fiber available from DSMDyneema BVm Heerlen, Netherlands, Spectra® fiber available fromHoneywell in Morristown and Pegasus UHMWPE fiber available from PegasusMaterials in Shanghai, China. The UHMWPE fibers provide excellentstrength and modulus with a small filament size to provide excellentballoon coverage and maintaining a minimal profile. However, whenmelted, the fibers lose their high molecular orientation andconsequently, may also lose their bond tensile strength at the proximalwaist portion 16 a and/or the distal waist portion 16 b of the balloon10 at a thermal bond interface. Additionally coatings may be optionallyapplied to the balloon, such as between the outer surface of the balloonand the braid, over the outer surface of the braid or both. In someembodiments, the coating includes a thermoplastic elastomer. In otherinstances, the coating includes a thermoplastic polyurethane. In someinstances, the coating of a thermoplastic polyurethane may be applied tothe balloon 10 using a suitable technique (e.g., dip coating, spraycoating, rolling, or the like) prior to braiding and is also applied tothe balloon/braid after braiding.

The catheter shaft 30 may be formed from any suitable shaft material.Examples include, but are not limited to, polytetrafluoroethylene(PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylenepropylene (FEP), polyoxymethylene (POM, for example, DELRIN® availablefrom DuPont), polyether block ester, polyurethane (for example,Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC),polyether-ester (for example, ARNITEL® available from DSM EngineeringPlastics), ether or ester based copolymers (for example,butylene/poly(alkylene ether) phthalate and/or other polyesterelastomers such as HYTREL® available from DuPont), polyamide (forexample, DURETHAN® available from Bayer or CRISTAMID® available from ElfAtochem), elastomeric polyamides, block polyamide/ethers, polyetherblock amide (PEBA, for example available under the trade name PEBAX®),ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE),Marlex high-density polyethylene, Marlex low-density polyethylene,linear low density polyethylene (for example REXELL®), polyester,polybutylene terephthalate (PBT), polyethylene terephthalate (PET),polytrimethylene terephthalate, polyethylene naphthalate (PEN),polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI),polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyparaphenylene terephthalamide (for example, KEVLAR®), polysulfone,nylon, nylon-12 (such as GRILAMID® available from EMS American Grilon),perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin,polystyrene, epoxy, polyvinylidene chloride (PVdC),poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS50A), polycarbonates, ionomers, biocompatible polymers, other suitablematerials, or mixtures, combinations, copolymers thereof, polymer/metalcomposites, and the like. In some embodiments the sheath can be blendedwith a liquid crystal polymer (LCP). For example, the shaft materialmixture can contain up to about 6 percent LCP. In some embodiments, thecatheter shaft 30 is formed from a polyamide, for example Grilamid®which is commercially available from EMS-Grivory.

In an example, the inner surface of at least one of the proximal anddistal waist portions 16 a, 16 b are thermally bonded to an outersurface of a distal portion of the catheter shaft 30 prior to bonding ofthe fiber braid 20 to the proximal and distal waist portions 16 a, 16 b.As used herein, thermal bonding refers to the melting of materials or aportion thereof by applying heat, laser, welding or some combinationthereof, to obtain a mixing or bonding of the materials at the materialinterface. An inner surface of the fiber braid 20 is then adhesivelybonded to an outer surface of the proximal and distal waist portions 16a, 16 b.

A suitable adhesive may be employed for bonding the fiber braid 20 tothe proximal and distal waist portions 16 a, 16 b and include, but arenot limited to, for example, thermoset adhesives that suitably cureeither via a chemical reaction or irradiation. Specific examples ofsuitable thermoset adhesives include moisture cure and radiation curesuch as ultraviolet (UV) radiation cure, e-beam, and the like. In someembodiments, the adhesive is a thermoset cyanoacrylate adhesive. Aparticular example is Loctite 4011 available from Henkel Adhesives.

FIG. 2 is a partial cross-section of the balloon 10 disposed on thedistal portion of the catheter shaft 30 wherein an inner surface of thefiber braid 20 is adhesively bonded to an outer surface of the proximalwaist portion 16 a and an inner surface of the proximal waist portion 16a is thermally bonded to an outer surface of a distal portion of thecatheter shaft 30. This is also illustrated in cross-section in FIG. 3which is taken at section 3-3 from FIG. 2. An adhesive 50 may bedisposed between the outer surface of the proximal waist portion 16 aand the inner surface of the fiber braid 20. The proximal waist portion16 a may be secured to the catheter shaft 30 with another type of bondsuch as, for example, a thermal bond which is shown schematically inFIGS. 2 and 3 as a thermal bond region 51. As indicated above, a coating(not shown) may be disposed along the exterior of the fiber braid 20.

FIGS. 4-10 illustrate an example method of manufacturing the ballooncatheter 11 and/or other balloon catheters. FIG. 4 is a side view of aportion of the balloon 10 having the proximal cone portion 14 a and theproximal waist portion 16 a prior to application of the fiber braid 20and prior to disposition on the catheter shaft 30. FIG. 5 is a side viewof the balloon 10 having the proximal cone portion 14 a and the proximalwaist portion 16 a after application of the fiber braid 20 onto theballoon 10. In this embodiment, the fiber braid 20 extends beyond theproximal waist portion 16 a of the balloon 10 resulting in a portion 22of fiber braid 20 that is unsupported by the balloon 10. In this case,the proximal waist portion 16 a of the balloon 10 is shown and theunsupported portion 22 of the fiber braid 20 is shown extendingproximally beyond the proximal end of the proximal waist portion 16 a. Amandrel 62 (not shown in FIG. 5, can be seen in FIG. 6) may be placedadjacent to or otherwise underneath the unsupported portion 22 of thefiber braid 20. The unsupported portion 22 of the fiber braid 20 may betrimmed to a desired length as shown in FIG. 6.

The temporarily unsupported portion 22 of the fiber braid 20 (and aportion of the fiber braid 20 that is supported by the proximal waistportion 16 a) is then retracted, pushed back, otherwise rolled back toexpose a portion of the proximal waist portion 16 a to allow for thermalbonding of the balloon of the proximal waist portion 16 a to thecatheter shaft 30 shown in FIG. 7. In this example, the mandrel 62 isremoved and the catheter shaft 30 is disposed within the proximal waistportion 16 a. Heat can be applied to thermally bond the proximal waistportion 16 a to the catheter shaft 30. After thermal bonding, adhesive50 is then applied to the exposed proximal waist portion 16 a as shownin FIG. 8. The fiber braid 20 (including portion 22) is then movedproximally to cover the proximal waist portion 16 a as shown in FIG. 9and the fiber braid 20 is now bonded to the proximal waist portion 16 avia the adhesive (and the proximal waist portion 16 a is thermallybonded to the catheter shaft 30). In some instances, the fiber braid 20(e.g., the unsupported portion 22 of the fiber braid 20) may be trimmedto a desired length and a fillet application of adhesive 35 may beapplied at the proximal bond site as shown in FIG. 10.

This method preserves the molecular orientation of the fiber braid 20 byavoiding application of heat which may adversely affect some propertiesof the balloon 10 such as tensile and burst pressure data.

In at least some instances, the balloon catheter 11 may be formed usinga suitable process. For example, the catheter shaft 30 may be formed bybonding an inner and an outer catheter shaft assembly having a duallumen shaft formed from Grilamid®. A balloon parison (tubular member)formed of Pebax® 7033 having an 8 mm diameter may be stretched, placedin a balloon mold and formed by radial expansion. The tubes mayalternatively have 4 mm or 12 mm diameters. The parison may be stretchedat a tube stretch ratio of 3.0. The raw tube had an inner diameter (ID)of 0.0551″ and an outer diameter (OD) of 0.0708″. The stretched tube mayhave an ID of 0.056″ and an OD of 0.059″. A mandrel may be installed andthe balloon parison may be inflated to 13 psi to form the balloon 10.The balloon 10 may be plasma treated with oxygen, and dip coated with2.5% solids Lubrizol SG 60D thermoplastic polyurethane in a cosolventblend of 50% toluene/50% tetrahydofuran. The plasma treatment may beconducted in a Nordson-March Plasma Chamber at a 100 sccm flow rate,base pressure 100 mtorr, 250 Watts, 90 Seconds times four cycles. Thecoating thickness may be about 4 μm. The dipping process may take up tofour repeat cycles to achieve the desired thickness with 10 minutes inbetween each cycle at a dip down and up speed of 50 inches/minute with ahold time of 2 seconds in a 100 mL graduated cylinder. The balloon 10may then braided with an ultra high molecular weight, highly orientedpolyethylene (UHMWPE) fiber braid 20 and again plasma treated and dipcoat braided balloon in 50:50 toluene:THF solvent with 2.5% solidsLubrizol SG 60D TPU to a thickness of 4 μm. The proximal and distalwaist portions 16 a, 16 b may be trimmed, and the balloon 10 may beinstalled onto the inner and outer shaft assembly of the catheter shaft30. The portion of the fiber braid 20 located on the proximal waist anddistal waist portions 16 a, 16 b may be moved distally from each waistenough to enable thermal bonding of the proximal waist and distal waistportions 16 a, 16 b to inner/outer shafts of the catheter shaft 30. Adistal tip can optionally be installed at this point, and the fiberbraid 20 may be moved back over the proximal and distal waist portions16 a, 16 b (e.g., where thermal bonds are present between the proximaland distal waist portions 16 a, 16 b and the catheter shaft 30), andadhesively bonded to the proximal and distal waist portions 16 a, 16 bof the balloon 10.

FIGS. 11 through 21 illustrate an alternative example method of makinganother example balloon catheter 111 that may be similar in form andfunction to other balloons catheters 111 disclosed herein. The processmay utilize a removable mandrel 62 that may be positioned adjacent aproximal waist portion 116 a of a balloon 110. The mandrel 62 and theballoon catheter 111 may be placed in a balloon holder 60 as shownschematically in FIG. 11 for waist trimming. In at least some instances,the mandrel 62 has a flared end that can be positioned adjacent to theproximal waist portion 116 a to prevent the waist cutting assembly fromnicking the catheter shaft 130 (not shown in FIG. 11, can be seen inFIG. 13). FIG. 12 is a view of the flared end of the mandrel 62 adjacentto the proximal waist portion 116 a. The flared end may be formedintegrally with the mandrel 62 or a washer or similar structure may bedisposed thereon.

The proximal waist portion 116 a may then trimmed from the fiber braid120 at the mandrel 62 using a cutting member as shown in FIG. 13. Theballoon catheter 111 is then removed from the balloon holder 60. Aballoon protector 80 can be slid in a distal direction over the proximalend of the catheter shaft 130 and over the proximal waist portion 116 aas illustrated in FIGS. 14 and 15.

Adhesive 150 may be applied at the proximal portion of the proximalwaist portion 116 a. The flared portion of the mandrel 62 results in thefiber braid 120 having a slightly flared end where the fiber braid 120terminates at the proximal portion of the proximal waist portion 116 a,which also allows adhesive to seep below the fiber braid 120 onto theunexposed proximal waist portion 116 a as shown in FIG. 16. The balloonprotector 80 is then slid proximally over the proximal waist portion 116a and the catheter shaft 130 which squeezes out excess adhesive 150 asshown in FIGS. 17 and 18. The adhesive 150 may be a thermoset adhesiveas discussed above. In some instances, the adhesive is an ultraviolet(UV) cure adhesive. In this embodiment, the balloon protector 80 isselected to as to be transparent to UV radiation, such as a clear Teflonmaterial so that the adhesive 150 can be cured with the balloonprotector 80 in place. The balloon protector 80 may be removed as shownin FIG. 19. The cured adhesive may leave a step 152 at the proximal endof the fiber braid 120 on the proximal waist portion 116 a. A fillet 154of adhesive may be applied to smooth out the step 152 as shown in FIG.20 and smoothed out over the proximal end of the fiber braid 120. Theadhesive fillet 154 can then also be UV cured.

FIG. 21 is a side view of the distal end of the balloon catheter 111illustrating the catheter shaft 130, the adhesive fillet 154, theproximal waist portion 116 b, and the proximal cone portion 114 b of theballoon 110. The assembly is shown disposed on a guidewire 90. This mayalso be a removable mandrel or other tubular member.

It should be understood that this disclosure is, in many respects, onlyillustrative. Changes may be made in details, particularly in matters ofshape, size, and arrangement of steps without exceeding the scope of thedisclosure. This may include, to the extent that it is appropriate, theuse of any of the features of one example embodiment being used in otherembodiments. The invention's scope is, of course, defined in thelanguage in which the appended claims are expressed.

1. A method of making a catheter assembly, the method comprising: disposing a fiber braid about a balloon, the balloon comprising a cone portion, a waist portion and a body portion, an end of the fiber braid being terminated at a predetermined point relative to the waist portion; disposing the balloon on a catheter shaft; applying heat to at least a portion of the waist portion to thermally bond an inner surface of the waist portion to an outer surface of the catheter shaft; and after thermally bonding the waist portion and the catheter shaft, then applying adhesive to bond an inner surface of the fiber braid to the outer surface of the waist portion.
 2. The method of claim 1, further comprising trimming the end of the fiber braid to a predetermined length.
 3. The method of claim 2, further comprising applying additional adhesive to the end of the fiber braid to provide a smooth transition from the fiber braid to the catheter shaft, and curing the additional adhesive.
 4. The method of claim 1, wherein the predetermined point relative to the waist portion is a point beyond the waist portion in a direction away from the body portion.
 5. The method of claim 1, wherein a first section of the fiber braid is supported by the waist portion and a second section of the fiber braid extends beyond the waist portion in a direction away from the body portion such that the second section is unsupported by the waist portion, wherein applying heat to the waist portion includes first retracting at least the second section of the fiber braid and a region of the first section of the fiber braid toward the body portion to expose at least some of the waist portion before thermally bonding the waist portion to the catheter shaft.
 6. The method of claim 5, wherein applying adhesive includes applying adhesive to the exposed waist portion, then moving the second section of the fiber braid back over the waist portion, and curing the adhesive.
 7. The method of claim 1, wherein disposing the balloon on the catheter shaft includes welding the waist portion to the catheter shaft, braiding the fiber braid over the balloon and the catheter shaft, trimming the fiber braid at a predetermined location, and applying the adhesive to the waist portion, to the inner surface of the fiber braid at the waist portion at the predetermined location, or both.
 8. The method of claim 1, wherein the fiber braid comprises a molecularly oriented ultra high molecular weight polyethylene.
 9. The method of claim 1, wherein the adhesive is a non-heat curing adhesive.
 10. The method of claim 9, wherein the non-heat curing adhesive is an ultraviolet (UV) curing adhesive, wherein adhesively bonding the inner surface of the fiber braid to the outer surface of the waist portion includes subjecting the waist portion to UV light.
 11. A method of making a catheter assembly, the method comprising: disposing a fiber braid about a balloon, the balloon comprising a body portion, a waist portion, and a cone portion disposed between the body portion and the waist portion, an end of the fiber braid being terminated at a predetermined point relative to the waist portion; disposing the balloon on a catheter shaft; retracting at least a section of the fiber braid toward the body portion to expose a section the waist portion; applying heat to at least the exposed section of the waist portion to create a thermal bond between an inner surface of the waist portion and an outer surface of the catheter shaft; and after creating the thermal bond, then moving the retracted section of the fiber braid back over the waist portion, and adhesively bonding an inner surface of the fiber braid to the outer surface of the waist portion.
 12. The method of claim 11, wherein the fiber braid is terminated at a point beyond the waist portion in a direction away from the body portion, resulting in an unsupported section of the fiber braid unsupported by the waist portion.
 13. The method of claim 12, wherein retracting at least a section of the fiber braid includes retracting the unsupported section of the fiber braid.
 14. The method of claim 11, wherein after adhesively bonding the inner surface of the fiber braid to the outer surface of the waist portion, the method further comprises applying additional adhesive to the end of the fiber braid to provide a smooth transition from the fiber braid to the catheter shaft, and curing the additional adhesive.
 15. The method of claim 11, wherein the fiber braid comprises a molecularly oriented ultra high molecular weight polyethylene.
 16. The method of claim 11, wherein adhesive bonding includes applying a non-heat curing adhesive.
 17. The method of claim 16, wherein the non-heat curing adhesive is an ultraviolet (UV) curing adhesive, wherein adhesively bonding the inner surface of the fiber braid to the outer surface of the waist portion includes subjecting the waist portion to UV light.
 18. A method of making a catheter assembly, the method comprising: disposing a fiber braid about a balloon, the balloon comprising a cone portion, a waist portion and a body portion, an end of the fiber braid being terminated and flared at a predetermined point relative to the waist portion; disposing the balloon on a catheter shaft; sliding a balloon protector distally over the waist portion of the balloon toward the body portion, exposing a section of the waist portion; applying a non-heat curing adhesive to a proximal region of the exposed section of the waist portion and allowing the adhesive to flow under the flared end of the fiber braid; sliding the balloon protector proximally over the waist portion to squeeze out excess adhesive; and curing the adhesive.
 19. The method of claim 18, wherein the non-heat curing adhesive is a UV curing adhesive, and the balloon protector is transparent to UV radiation.
 20. The method of claim 18, wherein curing the adhesive results in a step between the end of the fiber braid and the waist portion, wherein the method further comprises adding additional adhesive to smooth out the step. 